The invention concerns a method for feeding an optical cored wire into a molten metal bath and an immersion system and an immersion nozzle to carry out the method. The optical cored wire (6) is decoiled, a feeding and straightening device (4) with a plurality of rollers (20, 21) conducts feeding of the optical cored wire (6) in a feeding direction towards the metal bath (11) as well as a first straightening of the optical cored wire (6), and subsequently a separated further plurality of non-motor driven nozzle straighteners (13) arranged between the feeding and straightening device (4) and the metal bath (11) conducts a second straightening of the optical cored wire (6). Very high precision of temperature measurement can thereby be achieved.

The present disclosure provides a metallurgical electric furnace, and a smelting method for the metallurgical electric furnace. The metallurgical electric furnace includes a furnace body, an oxygen lance and a coal lance, wherein the furnace body is provided with a furnace chamber; the oxygen lance is located on a side wall of the furnace chamber and is used for blowing oxygen into the slag promoting the smelting process, and the outlet of the oxygen lance is higher than the slag; and the coal lance is located on the side wall of the furnace chamber beside the oxygen lance and is used for spraying coal into the slag, and the outlet of the coal lance is higher than the slag.

This invention relates to a method of operating a top submerged lance furnace, and more particularly but not exclusively to a method of coating an end of a lance of a top submerged lance furnace with a slag layer, as well as a method of maintaining a uniform heat distribution about the periphery of the lance of the top submerged lance furnace. In terms of the method, the lance is caused to rotate, and a fluid is passed through the lance before it is inserted into the molten material bath inside the crucible.